1. Field of the Invention
The present invention relates to a silicon pressure micro-sensor of the capacitive type.
2. Discussion of the Related Art
Over the last years, new silicon micro-sensors have been developed, taking advantage of the silicon etching techniques developed for the manufacturing of semiconductor electronic components. Initially, such microsensors were formed by the combination of suitably etched silicon plates and thin glass plates serving as airtight chamber or as separating insulating plates inserted between the silicon plates, these glass plates bearing various metal electrode patterns.
An exemplary prior art pressure micro-sensor is formed by the device described in French application 90/09,468 filed in the name of the applicant. In this prior art sensor, the active elements are formed by a sandwich of three silicon plates but the whole structure is delineated by two external glass plates which define a controlled atmosphere region.